Mannitol vs HS to Treat ICHT After Severe TBI : Comparison on PtiO2 and Microdialysis Values

Mannitol Versus Hypertonic Saline to Treat Intracranial Hypertension After Severe Traumatic Brain Injury : a Comparative Study on the Effects on PtiO2 and Microdialysis Values

The purpose of this study is to determine whether hypertonic saline is as much effective as mannitol to treat intracranial hypertension after traumatic brain injury and has at least the same effects on PtiO2 and cerebral metabolism studied through microdialysis.

Mannitol is frequently used to treat intracranial hypertension after TBI. However, it can be deleterious, particularly through hyperdiuresis and risks of hypovolemia. It also needs volume compensation and induces logistical problem because of needs of high infused volume to achieve osmolar load and avoid hypotension. Finally, some recent studies tend to prove superiority of hypertonic saline versus mannitol on the prognosis of TBI. especially through modulation of inflammatory reactions mechanisms and apoptosis. We would like to prove non inferiority of hypertonic saline versus mannitol after TBI to allow its large utilization, especially by field military doctors with specific logistical problems. For that, more than the single Intracranial Pressure, we want to study effects of HS vs mannitol not only on PtiO2 but also on cerebral microdialysis which gives informations on focal metabolism with profiles of ischemia, metabolic crisis, hyperglycolysis (possible reflect of neuronal restoration) and normality.

Inclusion Criteria: Severe Traumatic brain injury monitored with ICP, PtiO2 and cerebral microdialysis And ICP> 20 mm Hg needing osmotherapy And approval of the next of kind Exclusion Criteria: Bilateral fixed dilated pupils Contra-indication to multimodal neuromonitoring Previous CNS disease Contra-indication to HS (cardiac insufficiency,...) Natremia > 155 mmol/L or osmolarity > 320 mOsm/L

Vialet R, Albanese J, Thomachot L, Antonini F, Bourgouin A, Alliez B, Martin C. Isovolume hypertonic solutes (sodium chloride or mannitol) in the treatment of refractory posttraumatic intracranial hypertension: 2 mL/kg 7.5% saline is more effective than 2 mL/kg 20% mannitol. Crit Care Med. 2003 Jun;31(6):1683-7. doi: 10.1097/01.CCM.0000063268.91710.DF.

Sakowitz OW, Stover JF, Sarrafzadeh AS, Unterberg AW, Kiening KL. Effects of mannitol bolus administration on intracranial pressure, cerebral extracellular metabolites, and tissue oxygenation in severely head-injured patients. J Trauma. 2007 Feb;62(2):292-8. doi: 10.1097/01.ta.0000203560.03937.2d.

Soustiel JF, Vlodavsky E, Zaaroor M. Relative effects of mannitol and hypertonic saline on calpain activity, apoptosis and polymorphonuclear infiltration in traumatic focal brain injury. Brain Res. 2006 Jul 26;1101(1):136-44. doi: 10.1016/j.brainres.2006.05.045. Epub 2006 Jun 19.